Using up weed control technologies one at a time - recipe for disaster

Most weed scientists I know are doing their research with the 2,4-D and dicamba traits, hoping we can make them work in the field. I do not talk to any that are enthusiastic that we can. Guarded optimism is about as close as it gets.

I have had several interesting comments about the recent column in which I talked about weeds driving the seed business. I wrote that I do not believe basic industry could come together to support each other’s technologies is a diverse system. I hope I am wrong, because I believe that absolutely has to happen if we are to stop using up technologies one at the time.

If we go forward with only one technology — regardless of which one it is — I believe it will have a three- to five-year lifespan. It could be shorter.

That is why it looks so challenging for the seed business, because a technology could be dead before the seed industry gets completely geared up on variety choice and availability. We are at a critical juncture with the LibertyLink technology as we are being forced to abuse it in the South. If we get resistant Palmer pigweeds before we get an alternative technology to rotate with, things will get far more challenging than they already are.

As I visit with university counterparts working with the dicamba and 2,4-D traits, most do not even want to talk about glyphosate combinations with dicamba or 2,4-D, but rather are far more excited about glufosinate (Liberty) in combination with these.

The reasons are simple. Glyphosate doesn’t control the driver weeds any more. If we only go forward with glyphosate plus dicamba or glyphosate plus 2,4-D, then those stack traits really have only a single mode of action on the driver weeds.

Even though dicamba and 2,4-D have activity on Palmer pigweed and waterhemp, they are not as good as you might think. However, when either of these are mixed with glufosinate, they have dynamite activity.

The other trait that is coming is the HPPD tolerance trait. Again, at this point that trait has much more potential to control the driver weeds stacked with glufosinate than it does with glyphosate. If the dicamba, 2,4-D and HPPD traits all come forward, we already know up front there are resistance genes for these already in the pigweed populations.

I sincerely hope we do not have resistance to glufosinate or Liberty in 2012. If it is not the broad-spectrum herbicide that carries us into the future, then we do not have one. That and the fact we know resistance is already out there for each of the new traits makes it imperative that industry work together. That should have been a major theme at the National Summit on Strategies to Manage Herbicide Resistant Weeds, but it was not mentioned by a single speaker.

Most weed scientists I know are doing their research with the 2,4-D and dicamba traits, hoping we can make them work in the field. I do not talk to any that are enthusiastic that we can. Guarded optimism is about as close as it gets. We must find a way to make each of these work, because future options are limited. Soybeans without the dicamba trait is the most sensitive plant to dicamba that I know of. Cotton without the 2,4-D trait is the most sensitive plant to 2,4-D that I know of. That represents a huge challenge for these technologies.

New formulations are being developed and a lot of work is going into looking for better application technologies. I keep hoping the companies know something I don’t. If we cannot grow crops with and without a trait in close proximity, either one trait cannot be used at all or it dominates. Neither scenario is good. Diversity now is a must.

One bright spot is we have a new generation of excellent weed scientists coming along. Most of them do not yet know how good they can be. I remind them constantly that they will have to be much smarter than my generation.

I also think it is a bright spot that farmers are getting mad at the weeds. While my optimism is not very high that industry can work in concert with the new technologies, my confidence in the young guns in weed science and farmer ingenuity is high.